IGI Certificate Report Number: How to Verify Your Lab Diamond Is Authentic

Your IGI certificate report number is the unique identifier printed on your grading report and laser-inscribed on the diamond’s girdle. To confirm your lab diamond is authentic, locate that number on the physical certificate, match it to the inscription on the stone under 10x magnification, then enter it into IGI’s free “Verify Your Report” tool at igi.org. The verification form asks for three fields: report number, stone shape, and carat weight.

Sellers occasionally attach a legitimate-looking report to a stone it was never issued for, and the only way to catch that is to cross-reference the physical stone, the printed document, and IGI’s own database. A paper certificate is easy to copy; the laser inscription on the girdle is not. Doing both checks together closes that gap.

Where exactly is the IGI report number on the certificate?

The report number sits in the upper-left corner of the IGI grading document, labeled either “Report Number” or “Report ID.” IGI report numbers are typically 10 to 13 digits long, and the format has stayed consistent across IGI’s lab-grown diamond reports issued in recent years.

Below the report number you will find the issue date, the shape and cutting style, and the measurements of the stone. Those details matter later when you cross-check them against the physical diamond. If your certificate is the folded wallet-card version rather than the full-page document, the report number appears on the front panel in the same upper-left position.

Some retailers, including Ouros Jewels, include the report number directly in the product listing so you can look it up before the piece even arrives. That is worth doing: it lets you confirm the grading data matches what was advertised.

How do you find the laser inscription on the girdle?

The girdle is the narrow band running around the widest part of the diamond, between the crown (top) and the pavilion (bottom). IGI laser-inscribes the report number there using a process that leaves no visible damage to the stone.

To read it, you need a loupe or a jeweler’s microscope at 10x magnification. Hold the diamond table-down under good lighting and rotate it slowly while looking at the girdle edge. The inscription is usually a few millimeters long and appears as faint gray or white text against the polished surface. On a well-cut stone the inscription is legible within a few seconds of searching. If you cannot find it yourself, any local jeweler can locate it for you in under a minute.

The number you see inscribed should be an exact character-for-character match to the report number on your certificate. A single digit off means the stone and the certificate do not belong together.

How do you verify the report number at IGI.org?

Go to igi.org and navigate to the “Verify Your Report” page, which IGI keeps in the main menu under the “Reports” tab. Enter the three required fields: report number, stone shape (for example, round brilliant or oval), and carat weight as listed on your certificate.

On a confirmed match, IGI’s result page displays the full grading data from the original report, a scanned image of the certificate, and the issue date. If any of those three fields do not match what IGI has on file, the tool returns no result. That outcome does not always mean fraud; occasionally a very recently issued report takes a day or two to appear in the database. In that case, contact IGI directly with the report number and they can confirm it manually.

One thing to check on the result page: the 4Cs grades (cut, color, clarity, and carat weight) should match your printed certificate exactly. Any discrepancy between the online record and the paper document is a red flag worth investigating before accepting the purchase.

Why do all three sources need to agree for verification to hold up?

Cross-referencing the certificate, the girdle inscription, and IGI’s database is the only verification method that actually holds up, because each source catches a different category of problem. Matching just the certificate to the online database tells you the report is real but does not prove the stone in front of you is the one that was graded. Matching just the inscription to the certificate tells you the number was engraved correctly but does not confirm IGI issued that report for those exact grades.

When all three agree, you have confirmed that the report is genuine, the stone carries the correct inscription, and the grades on your certificate reflect what IGI actually measured. That three-way agreement is what authentication means in practice.

If you are shopping for IGI certified lab grown diamonds, each stone comes with a report number you can verify through this exact process before or after purchase.

What else is the IGI report number used for after purchase?

Authentication is not a one-time event. The report number is also the reference you will use when insuring the diamond, reselling it, or having it reset into a new setting. Jewelers and appraisers ask for it as a matter of routine, and having it on hand speeds up every one of those conversations.

Keep a digital photo of your certificate alongside the physical document. If the paper is lost, IGI can reissue a replacement report for a fee, using the original report number to pull the grading data from their archive. The number itself does not expire.

For pieces like IGI certified round lab grown diamond stud earrings, each stone in the pair carries its own individual report number, so the verification process applies to both stones separately.

The Girdle Inscription Is What Makes Verification Airtight

A certificate alone proves a diamond was graded. The girdle inscription proves the diamond in your hand is the one that was graded. Used together with IGI’s online database, those two sources give you a complete chain of evidence that no paper copy can replicate.

The verification steps are straightforward: find the report number on the upper-left of the certificate, read the matching inscription on the girdle under magnification, and enter both into IGI’s online tool. When IGI’s result page returns the grading data, stone image, and issue date that match your certificate, the diamond is confirmed authentic.

Frequently Asked Questions

What does an IGI report number look like, and how long is it?

An IGI report number is a string of 10 to 13 digits printed in the upper-left corner of the grading document, labeled “Report Number” or “Report ID.” The format is purely numeric with no letters or hyphens. The same number is laser-inscribed on the diamond’s girdle and is the key you enter into IGI’s online verification tool.

Can I verify an IGI report number without the physical diamond in front of me?

Yes. IGI’s “Verify Your Report” tool at igi.org only requires the report number, stone shape, and carat weight. You do not need the physical stone to check whether a report is genuine. However, confirming that the stone you received matches the report still requires reading the girdle inscription, which does require the diamond.

What should I do if the girdle inscription does not match the certificate report number?

Stop the transaction and contact the seller immediately. A mismatch means either the wrong certificate was provided or the inscription was altered, both of which are serious problems. Ask the seller to explain the discrepancy in writing. If the stone was purchased and already delivered, contact IGI directly with both numbers so they can investigate.

Does every IGI certified lab grown diamond have a girdle inscription?

In most cases, yes. IGI standard practice for lab-grown diamond reports includes laser-inscribing the report number on the girdle. Occasionally a very small stone, typically under 0.18 carats, may not carry a legible inscription due to size constraints. Your certificate will note whether an inscription was applied.

How is an IGI report different from a GIA report for a lab grown diamond?

Both IGI and GIA grade lab-grown diamonds using the same 4Cs framework: cut, color, clarity, and carat weight. IGI has historically been one of the most widely used labs for lab-grown diamond certification, and its reports tend to be priced more accessibly for consumers. GIA introduced lab-grown diamond grading more recently. Either report is verifiable online through the issuing lab’s own database.